In known mobile communications systems, such as the GSM (Global System for Mobile communications), it is known for mobile stations to take radio link measurements during progress of a call, and to report these measurements to the serving base station. The base scion uses these downlink measurement reports in order to determine when a handover is required.
Handover is initiated by the base station using radio sub-system criteria (signal strength level, link quality, link distance, etc) as well as network directed criteria (e.g. current traffic loading per cell, maintenance requests, etc).
In addition, current networks such as GSM networks include a mobile switching center (MSC), a second generation component in the form of a large, central switch.
Third generation systems are proposed in which various levels of service are provided and in which the MSC functionality is provided in a distributed processing environment, rather than in the form of a central switch.
It would be desirable to provide a more flexible and sophisticated approach to radio resource allocation. It would also be desirable to provide for the re-use of existing mobile network elements, in particular base stations, whilst providing enhanced radio resource signalling functionalities.